Smartphone Web and Internet support
One of the iPhone's revolutionary advances was in bringing the Web to mobile devices in a capable, effective way. All of a sudden, the mobile Web was real.
The WebKit browser that underlies the iPhone's Web experience is now used by the Palm Pre and Android devices, and it seems destined for BlackBerry.
For now, however, the BlackBerry series are the only holdouts for the old, hard-to-use mobile Web.
The BlackBerry OS's ability to reformat Web pages into a stack helps overcome some of its inability to deal with real Web pages, but it's no substitute for the real thing.
The Motorola Droid's lack of multitouch support makes navigating Web pages awkward; furthermore, the Droid's multistep process to copy text and the inability to copy graphics fall short of the iPhone's standards.
Likewise, the ability to access Internet services like Facebook, search, YouTube, and so on (another area iPhone pioneered) is pretty much standard across all modern mobile devices today.
The one common Web technology in which the iPhone OS is at a disadvantage is Flash Player support - it doesn't have it.
Neither does the Droid. The other devices can display Flash video. All but the BlackBerrys can display QuickTime Video, though there's a third-party app that lets the BlackBerry view QuickTime videos.